What makes these exposures a source of infection is probably not any one exposure but the cumulative nature of being exposed frequently over the course of time.
这些接触是一个感染源，也许这并不是因为任何一次接触，而是长期经常接触的累积性质所致。
Conclusions Imaging procedures are an important source of exposure to ionizing radiation in the United States and can result in high cumulative effective doses of radiation.
结论：在美国，影像操作是一个重要的电离辐射暴露来源，并可导致较高的辐射累积有效剂量。
By using this model, the current cumulative oil generating intensity and amount for immature source rocks of Qianjiang formation were calculated in JJ, QQ, XX Depressions, the Jianghan Basin.
应用该模型测算了江汉盆地JJ、QQ、XX凹陷潜江组未熟烃源岩在现今的累积生油强度和生油量。
Technological innovation diffusion is the "cumulative" of technological innovation, and also the source of the growth of technological level and macro economic growth.
技术创新扩散是技术创新的“累积”效应，是宏观技术水平提高与国民经济增长的源泉。
Technological innovation diffusion is the "cumulative" of technological innovation, and also the source of the growth of technological level and macro economic growth.
技术创新扩散是技术创新的“累积”效应，是宏观技术水平提高与国民经济增长的源泉。
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